This invention relates to a family of polypeptides having properties which ameliorate or retard effects of aging in mammals, particularly by reducing age related increase in fat, and/or reducing age related decrease in lean body mass.
Obesity, defined as an excess of body fat relative to lean body mass, is thought to be associated with important psychological and medical morbidities, the latter including cardiovascular disease, hypertension, elevated blood lipids, and Type II or non-insulin-dependent diabetes melitis (NIDDM). Despite a vast amount of research, the molecular factors regulating food intake and body weight balance are incompletely understood. Myriad approaches to reducing obesity and associated effects have been attempted over the years. There remains a persistent need for addressing these problems, but a particularly useful approach would be one that involves a reduction in the general increase in the amount of body fat relative to lean body mass that occurs with aging.
In one broad aspect, the present invention is a method of ameliorating effects of aging in an animal. The method includes administering to the animal an effective amount of a chemical compound that includes a synthetic polypeptide comprising an amino acid sequence that has 10+q amino acids, wherein, under physiological conditions, residues numbered n, n+4, n+9 are positively charged amino acids, residues numbered n+3, n+7 are negatively charged amino acids, wherein the remaining amino acids are nonpolar amino acids or uncharged polar amino acids, wherein n is an integer from 1 to 1+q and q is a whole number greater than or equal to zero.
When it is stated herein that an amino acid is positively charged under physiological conditions, it is meant that the side chain group of the amino acid within the polypeptide, e.g. the amino group of a lysine, would be at least 10% protonated in an aqueous solution of pH about 6.5 and ionic strength 0.1. Likewise, when it is stated herein that an amino acid is negatively charged under physiological conditions, it is meant that the side chain group of the amino acid within the polypeptide, e.g. the carboxyl group of aspartate, would be at least 10% deprotonated under such conditions.
Preferably, the animal to which the polypeptide is administered is a mammal, most preferably a human.
In one aspect, ameliorating effects of aging includes reducing an age-related increase in fat.
In another, ameliorating effects of aging includes reducing an age-related decrease in lean body mass.
In yet another, ameliorating effects of aging includes reducing age-related reduction in bone mineral content-body weight ratio of the subject.
In yet another, ameliorating effects of aging include includes reducing age-related reduction in lean body mass-body weight ratio of the mammal.
There are preferred embodiments of the polypeptide, particularly one in which any one or more of the following is true: the amino acid at position n is arginine; n+1 is threonine or alanine; n+2 is asparagine or glutamine; n+3 is glutamic acid or aspartic acid; n+4 is histitdine, n+5 is threonine or alanine; n+6 is alanine or glycine; n+7 is glutamic acid or aspartic acid; n+8 is cysteine, alanine, tyrosine or serine; and n+9 is lysine. Preferably all of these conditions are met by the polypeptide part of the chemical compound.
In particular embodiments, at least one of the following is true: the amino acid at position n is arginine; n+3 is glutamic acid or aspartic acid; n+4 is histitdine, n+7 is glutamic acid or aspartic acid; and n+9 is lysine. Again, these conditions can be met in any combination with each other.
In other embodiments, at least one of the following are true: the amino acid at position n+1 is threonine or alanine; n+2 is asparagine or glutamine; n+5 is threonine or alanine; n+6 is alanine or glycine; and n+8 is cysteine, alanine, tyrosine or serine, yet again in any combination with each other.
In other embodiments, the polypeptide includes the amino acid sequence identified as SEQ ID NO:2 or SEQ ID NO:3 wherein up to 26 amino acids of the sequence have been deleted provided that amino acids 5 to 14 of the sequence are not deleted, or a substituted variant thereof in which (i) a non-polar, aliphatic neutral amino acid has been substituted for another non-polar, aliphatic neutral amino acid, (ii) a polar aliphatic neutral amino acid has been substituted for another polar aliphatic neutral amino acid, (iii) a charged acidic amino acid has been substituted for another charged acidic amino acid, (iv) a charged basic amino acid has been substituted for another charged basic amino acid, (v) cysteine has been substituted by alanine, or (vi) a combination of substitutions (i)-(v) has been made, in which said synthetic polypeptide ameliorates effects of aging in an animal.
In other embodiments, the polypeptide includes a sequence of amino acids which is encoded by a DNA that specifically hybridizes with DNA encoding the polypeptide consisting of any of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, SEQ ID NO:17, SEQ ID NO:18, SEQ ID NO:19, and SEQ ID NO:20, and which polypeptide ameliorates effects of aging in a mammal or retards effects of aging in a mammal.
SEQ ID NO:2 is encoded by the nucleotide sequence designated SEQ ID NO:45, as follows:
A person skilled in the art will understand that, due to the well known degeneracy of the genetic code, that there are other coding sequences that encode SEQ ID NO:2. Further, the polypeptide fragments of the present invention are similarly encoded by corresponding portions of SEQ ID NO:45.
A DNA sequence encoding a polypeptide having SEQ ID NO:1 (unprotected version identified as SEQ ID NO:35) is identified as SEQ ID NO:54. DNA sequences encoding polypeptides have SEQ ID NOs: 2 to 9, and 11 to 20 are identified as SEQ ID NOs:45 to 53 and 55 to 63, respectively. Unprotected versions of polypeptides identified as SEQ ID NOs:1, 10 to 20 and 33 are identified as SEQ ID NOs: 35, 9, 34, 36 to 44 and 2, respectively.
In other embodiments, the polypeptide includes a sequence of amino acids selected from the following group of sequences: SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, SEQ ID NO:17, SEQ ID NO:18, SEQ ID NO:19, SEQ ID NO:20, and conservatively substituted variants of each of SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, SEQ ID NO:17, SEQ ID NO:18, SEQ ID NO:19 and SEQ ID NO:20 which ameliorate effects of aging in a mammal.
In particularly preferred embodiments, the polypeptide is one which ameliorates effects of aging in a mammal and includes a sequence of amino acids selected from the following group of sequences: SEQ ID NO:1, SEQ ID NO:2, SEQ ID NO:3, SEQ ID NO:4, SEQ ID NO:5, SEQ ID NO:6, SEQ ID NO:7, SEQ ID NO:8, SEQ ID NO:9, SEQ ID NO:10, SEQ ID NO:11, SEQ ID NO:12, SEQ ID NO:13, SEQ ID NO:14, SEQ ID NO:15, SEQ ID NO:16, SEQ ID NO:17, SEQ ID NO:18, SEQ ID NO:19, and SEQ ID NO:20.
In a particularly preferred embodiment, the polypeptide is one which ameliorates effects of aging in a mammal and includes SEQ ID NO:1.
Another aspect of the invention is a method of manufacturing a medicament for use in ameliorating effects of aging in a mammal. The method includes the following steps:
(a) providing a composition in dosage form, the composition containing a chemical compound of the present invention (see above);
(b) packaging the composition; and
(c) providing the package with a label instructing a user to administer the composition as a medicament for use in ameliorating effects of aging in a mammal, including any or all of the age-related effects described above.